----- Original Message -----
From: "Frank Ellermann" <nobody(_at_)xyzzy(_dot_)claranet(_dot_)de>
To: <ietf-822(_at_)imc(_dot_)org>
Cc: <ietf-smtp(_at_)imc(_dot_)org>
Sent: Thursday, July 07, 2005 9:54 PM
Subject: Re: OPES and Email
Tony Hansen wrote:
I don't know if you saw the recent I-D documents that came
out, entitled OPES SMTP Use Cases
(draft-ietf-opes-smtp-use-cases-02.txt).
Yes, I saw the announcement, and then decided that "somebody"
will probably explain what OPES is, I've not the faintest idea.
Simplistic terms from an SMTP standpoint - is a CALL OUT - like a CBV or
SINK or "HOOK" or "SHIM" or a "BLACKBOX" whatever you might want to call it
that calls a sub-process and comes back with a result.
If you read my messages, I've talking about it for a while :-)
It will have all the same issues like TIMEOUT considerations as well, which
I pointed out in a few message may be addressed using the 1xz response codes
to keep a client alive with a OPES callout is done.
In layman terms is is a 'service' or proxy that can be called by "any
protocol" for whatever purpose. The OPES SMTP Use Cases shows some of the
example "proxies" you can probably invent for SMTP.
CBV could be modeled as a OPES service for the MAIL FROM state, in fact the
entire SMTP state machine can be modeled for OPES as so:
SMTP level OPES hooks:
result = OPES_CONNECT(ip)
result = OPES_HELO(ip,helo)
result = OPES_MAIL(ip,helo,mfrom)
result = OPES_RCPT(ip,helo,mfrom,rcpt)
result = OPES_DATA(ip,helo,mfrom,rcpt,data)
accept post smtp OPES hooks:
result = OPES_POST_SMTP(ip,helo,mfrom,rcpt,data)
OPES for SMTP will have technical issues such as:
- Call out Timeouts
- Extended Response Codes/Text integration
Pretty much the same as a CBV which is basically a OPES like concept. From
a SMTP view point, a CBV is a OPES like concept.
You can also basically say SPF is a OPES hook too for the MAIL FROM and HELO
states:
spf-result = OPES_SPF(ip,helo)
spf-result = OPES_SPF(ip,mailfrom)
Same with SenderID/PRA for the DATA stata:
senderid-result = OPES_SENDERID(ip,data)
All the extended ideas for SMTP would be for all intent and purposes OPES
SMTP Use Cases.
Hope this provides some clue. :-)
--
Hector Santos, Santronics Software, Inc.
http://www.santronics.com